Noise level increaser for snap-action devices



J. w. WELSH 3,236,972 NOISE LEVEL INCREASER FOR SNAP-ACTION DEVICES Feb. 22, 1966 Filed Dec. 31, 1963 INVENTOR. ([4MES M h/sZJ/ BY w Wzb 77 e/vsm United States Patent Lamp Company, Kearney, N.J., a corporation of New Jersey Filed Dec. 31, 1963, Ser. No. 334,715 6 Claims. (Cl. 200-122) This invention relates to an improvement in snap-action devices of the vane type, and more particularly to a novel means for increasing the noise level of such devices.

Electrical snap-action devices are well known in the art for use in controlling electrical circuits such as automobile directional signal systems. Such a vane type snapaction device is described in US. Patent No. 3,088,012 issued April 30, 1963.

In automobile directional signal systems, operation of the system may be indicated to the driver by means of the blinking of a pilot light and/or by the audible clicking sound made by the snap-action device. Although the flickering of the pilot light may be suflicient at night to indicate the operation of the directional signal, during the daytime such flickering may not be noticeable to the driver. Many times, too, a malfunction of the release mechanism or a slight curvature in the highway will prevent the tripping of the cancelling mechanism, thereby causing the signal to operate constantly, unbeknownst to the driver. In many states, this is unlawful and may subject the vehicle operator to a fine.

Thus it is both desirable and necessary to have a highly audible means for indicating signal operation. Although, in operation, the snap-action device gives off an audible clicking sound, in many instances this sound cannot be heard over the many noises encountered in the operation of a motor vehicle. Attempts by automobile manufacturers to appreciably increase the decibel level of the flasher through the use of a sounding board type mounting have generally proven unsatisfactory. Other attempts to increase the noise level of flashers have also proven unsatisfactory.

The present invention overcomes these difficulties and accomplishes a noise level appreciably greater than present day commercial flashers.

It is thus a primary object of this invention to provide a simple and eflicient means for increasing the noise level in snap-action devices.

It is another object of this invention to provide means for appreciably increasing the noise level of vane type snap-action devices that is easily adjustable and that will not interfere in any way with the normal operation of the vane.

Other and additional objects and advantages of this invention will make themselves apparent from the following description and drawings wherein:

FIGURE 1 is a side perspective view of a vane type snap-action device showing it in completed form suitable for installation;

FIGURE 2 is a top cross-sectional view taken along line 22 of FIGURE 1;

FIGURE 3 is a bottom perspective view of the snapaction device;

FIGURE 4 is a side cross-sectional view taken along line 44 of FIGURE 3;

FIGURE 5 is a side cross-sectional view taken along line 55 of FIGURE 4, showing the contacts in a closed position;

FIGURE 6 is a side cross-sectional view similar to that of FIGURE 5, showing the contacts in an open position.

More particularly referring to the figures, the snapaction device is provided with a base 10 made from a rigid insulating material such as Bakelite. The base is provided with a shell 11 having a peripheral flange 11a adapted to register over the base 10 and is rolled or crimped to secure the shell to the base; the shell is preferably made of a metal such as aluminum, which may be suitably shaped and rolled or crimped.

Secured within the base member 10 are two electrical terminals 12 and 14, which have lugs 15 and 16 extending through the base and adapted to be inserted into an electrical socket.

Electrical terminals 12 and 14 are angled as at 17 within the base as shown in FIGURE 4 and have arms extending through the top of the base. The arm 30 of terminal 12 is centrally disposed within the base member 10 and extends perpendicular thereto. The arm 31 of terminal 14 protrudes through the base member 10 and has its flat surface perpendicular to arm 30. The protruding arm 31 is angled so that it crosses in front of and in spaced relationship to arm 30.

The snap-action vane 18 comprises a thin metallic piece of meal curved along its horizontal axis to provide a convexed front face and a concaved back face. The vane is constructed so that it is adapted to be bent inwardly against the curvature and tend to flatten out when a force is exerted at side edges 22 and 23; the vane is preferably constructed from a metallic compound substantially comprising nickel or nickel-cobalt, the latter metal being able to withstand excessively high temperatures and possessing the capability of being rolled to a very thin cross-section. The amount of curvature given to the vane depends upon the particular size of the vane and upon the parameter of the vane.

Ribbon 21, of very thin metal, is attached to vane 18 adjacent its side edges as at 24 and 25 by electrical spotwelding or the like. Ribbon 21 is preferably made of a high resistant metal such as a nickel-chromium alloy, which has a different coefficient of expansion than the vane itself. Ribbon 21 is afiixed to vane 18 in such a way as to stress vane 18 out of its normal curvature about its horizontal axis such that the vane takes on a saucer-like curvature which extends throughout most of the height of the vane and throughout a substantial part of its horizontal surface.

The bottom corners 19 and 20 of vane 18 are bent or angled inwardly so that part of the ribbon adjacent the edges 22 and 23 is bent inwardly. Such a bending of the vane after the ribbon has been attached helps assist in holding the ribbon because of the increased friction caused by the radius at the bend angle and tightens the ribbon to provide maximum static pulling force at ambient temperature.

Ribbon 18 is provided with an electrical contact 26 which has a height less than the height of the ribbon.

3 Angled arm section 31 of electrical terminal 14 is provided with a second contact 27 which is aligned with but horizontally spaced from contact 26 of ribbon 21.

Lever arm 28 is mounted on vane 18 adjacent to its upper edge. Arm 28 is preferably of any suitable flexible metal which may be affixed to vane 18 by electrical spot-welding or the like. Hammer 29, of any suitable insulator material such as epoxy-resin, is mounted on arm 28 at its free end 33. Ann 28 is mounted adjacent the upper edge of vane 18 since it is this portion of the vane that undergoes motion during the snap-action cycle. As shown in FIGURE 5, arm 28 is mounted on the convex side of vane 18 and is out of contact with shell 11 when vane 18 is in the snapped position. It will be understood that arm 28 could also be mounted on the concave side of vane 18 in which case hammer 29.would be in contact with shell 11 when vane 18 was in the snapped position and out of contact with shell 11 when vane 18 was in the unsnapped position. Arm 28 could also be mounted adjacent the side edges 22 or 23 of vane 18-, but such mounting would not produce as much motion of arm 28 during the snap-action cycle.

The concaved back face of vane 18 is attached to the perpendicular arm of arm 30 of terminal 12 by a weld or the like. The weld or the like holds vane 18 to terminal arm 30 and is preferably located in the center of the vertical axis of the wane, thus providing spaces above and below the concaved surface of vane 18 and the terminal arm 30. The operation of the snap-action device is as follows:

In FIGURES 2, 4, and 5, the snap-action device is shown just after ribbon 21 has cooled or is at substantially ambient temperature. Since the ribbon is cool, it is at minimum length and possesses a predetermined amount of kinetic energy. This energy is imparted to the vane at corners 19 and 20, reversing the normal curve of the vane and tending to buckle the center portion in a saucer-like fashion. The mechanical energy stored up in thevane at this position is at a maximum. Contacts 26 and 27 are normally closed. When electrical energy is applied to terminals 12 and 14 a circuit is completed through lug 15 and arm 30 of terminal 12 through contacts 26 and 27 and thence through arm 31 and lug 16 of terminal 17. Since ribbon 21 and vane 18 are of conductive material, current will flow through ribbon 21 and vane 18. Since the resistance of ribbon 21 is appreciably higher than vane 18 due to their relative sizes and materials, passage of current through the ribbon will cause it to expand at a much faster rate than the vane.

Expansion of the ribbon diminishes the forces the ribbon exerts at the edges of the vane, permitting the kinetic energy within the vane to cause the vane to seek its normal static position. As the ribbon expands, the vane approaches its normal curvature about the horizontal axis, withdrawing the ribbon with it and disengaging contacts 26 and 27. The vane then snaps into its static position where the forces are in equilibrium balance. This is shown in FIGURE 6. The vane 18 has its normal curvature with its bottom edge pressing against terminal arm 38.

Since there is no electric current flowing through the ribbon, its temperature decreases, causing it to contract. The ribbon exerts pressure on the corners of the vane, forcing it into a reverse curvature and buckling it at the center. This contraction continues until the vane resnaps, closing contacts 26 and 27. This snap-action operation is then repeated as long as the snap-action device has electrical energy applied across its terminals.

Referring now toFIGURES and 6, the operation of the snap-actiondevice is more clearly shown, as well as the action of the instant invention. Referring to FIG- URE 5, arm 28 with hammer 29 is an essentially horizontal position, out of contact with shell 11. As shown in FIGURE 6, when the snap-action device has been energized and vane 18 is caused to snap and thereafter to assume its static position, arm 28 with hammer 29 strikes shell 11, emitting a highly audible sound. 'The repetitive snapping action of vane 18 will cause arm 28 to repetitively strike shell 11. This repetitive striking of shell 11 by arm 28 creates a sound whose magnitude has been found to be substantially greater than the magnitude of sound created by present day vane type snap-action devices. This greatly increased sound level is substantially higher than the noise level of a motor vehicle in operation and is therefore readily discernible by the vehicle operator.

Arm 28 is so mounted on vane 18 that it does not interfer with the normal operation of the vane. Since arm 28 is preferably flexible, it may be adjusted slightly with great case without interfering with any other adjustment in the snap-action device. Hammer 29 is comprised of insulating material in order that current passing through vane 18 does not find an electrical path through arm. 28 to metallic shell 11. The striking of hammer 29 against shell 11 gives a high pitch long-lasting ringing sound which is many times greater the noise encountered in other vane type units.

It. is to be understood that the invention herein, although described in use with a particular type of vane snapaction device, may be used with any other vane type snap-action devices well known to those skilled in the art. It will also be appreciated that the form of the invention described herein is for illustration purposesonly, and other forms will be readily apparent to those skilled'in the art.

What is claimed is: j

1. In a snap-action device that includes a base, a snap-action vane mounted on said base and a shell mounted on said base and enclosing said vane, the improvement 7 comprising an elongated arm, said arm being mounted on one end thereof on said vane in proximity to an edge thereof and substantially perpendicular thereto, said arm provided with a hammer-like projection of nonconductive material on the other end thereof, such that movement of said hammer-like projection at the end of said elongated arm is amplified over the movement of said edge of said vane adjacent to which said arm is mounted thus to cause said hammer-like projection to strike said shell producing a highly audible sound.

2. In a snap-action device that includes a base, a snapaction vane mounted on said base and a shell mounted on said base and enclosing said vane, the improvement comprising an elongated lever armaflixed at one end thereof to said vane substantially perpendicular to and in proximity to the upper edge of said vane, said lever arm provided with a hammer-like pro ection at the other free end thereof, such that movement of said hammer-like projection at the end of said elongated lever arm is amplified over the movement of said upper edge of said vane adjacent to which said arm is mounted thus to cause said hammer-like projection to strike said shell producing a highly audible sound.

3. The improvement in snap-action devices of claim 2, whereby said hammer-like projection is of a nonconductive material.

4. The improvement in snap-action devices of claim 3, whereby said lever arm is of a flexible metal such that said arm may be easily adjusted.

5. In a snap-action device that comprises a curved resilient metallic vane, said vane being longitudinally curved about its transverse axis and having a convex front face and a concaved back face, a base, a pair of electrical terminals, said terminals having arm elements extending from said base in spaced relationship, one of said arms having an electrical contact, the concaved back face of said vane affixed the other of said arms at a centrally disposed area slightly off the longitudinal axis of said curved back face, an electrical ribbon aflixed the convex front face of said vane and provided with an electrical contact, said ribbon contact aligned with said arm contact, said base being provided a shell enclosing said electrical terminal arm ele- References Cited by the Examiner UNITED STATES PATENTS 1,269,005 6/ 1918 Schoenwolf 340384 2,141,775 12/1938 Varley 200113 2,820,120 1/1958 Flatt et al 200113 2,878,340 3/1959 Uhl 200 122 BERNARD A. GILHEANY, Primary Examiner.

10 L. A. WRIGHT, Assistant Examiner. 

1. IN A SNAP-ACTION DEVICE THAT INCLUDES A BASE, A SNAP-ACTION VANE MOUNTED ON SAID BASE AND A SHELL MOUNTED ON SAID BASE AND ENCLOSING SAID VANE, THE IMPROVEMENT COMPRISING AN ELONGATED ARM, SAID ARM BEING MOUNTED ON ONE END THEREOF ON SAID VANE IN PROXIMITY TO AN EDGE THEREOF AND SUBSTANTIALLY PERPENDICULAR THERETO, SAID ARM PROVIDED WITH A HAMMER-LIKE PROJECTION OF NONCONDUCTIVE MATERIAL ON THE OTHER END THEREOF, SUCH THAT MOVEMENT OF SAID HAMMER-LIKE PROJECTION AT THE END OF SAID ELONGATED ARM IS AMPLIFIER OVER THE MOVEMENT OF SAID EDGE OF SAID VANE ADJACENT TO WHICH SAID ARM IS MOUNTED THUS TO CAUSE SAID HAMMER-LIKE PROJECTION TO STRIKE SAID SHELL PRODUCING A HIGHLY AUDIBLE SOUND. 